Safety-switch.



'Withesss? I Q I Inventor: max Fuss.

M. PUSS. SAFETY" SWITCH. APPLICATION FILED APB.13, 190m 953 5. PatentedMar. 29, 19 10.

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Pig. 2.

UNITED STATES PATENT OFFICE.

MAX FUSS, OF BERLIN, GERMANY, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A.CORPORATION OF NEW YORK.

SAFETY-SWITCH.

Specification of Letters Patent. Patented Mar. 29, 1910.

Application filed April 13, 1906.

Serial No. 311,447.

To all whom it may concern:

Be it known that 1, MAX Foss, a subject of the King of Prussia, residingat Berlin, Germany, have invented certain new and useful Imprpvements inSafety-Switches, of which the following. is a specification.

The present invention relates to switches adapted to be operated orcontrolled manually to open and close a circuitv and to be operatedautomatically to interrupt the circuit under predetermined conditions inthe circuit, and comprises a novel construction and arrangement of partsto be hereinafter described and particularly pointed out in the claims.

In the accompanying drawing Figure 1 is a plan view of a preferred formof the present invention with part of the inclosing casing cut away;Fig. 2 is a side elevation of the same switch, the inclosing casing bemgshown in cross-section; Fig. 3 is a view similar to Fig. 2 except thatthe operating mechanism for the switch is shown in crosssection; Fig.4is a detail; Fig. 5 is a detail showing the movable switch memberreleasing a restraining catch on the operating handle.

Reference being had to the drawing, 1 indicates a base of insulatingmaterial which may conveniently be circular in shape. On the base arearranged fixed contact members 2, 3, 4 and 5.

6 and 7 are movable contact members consisting of spring fingers carriedupon a movable yoke 8 and adapted, respectively, to bridge the fixedcontacts 2, 3, and 4, 5.

An operating stem 9 passes loosely through" an opening 10 in the yoke 8,thus forming a support and guide for the movable contact members. A.sprin 11 surrounding the stem 9 and engaging with its opposite ends afixed support and the under side of the yoke 8 tends normally to moveand to maintain the movable contacts out of engagement with the fixedcontacts. Similarly, a spring 12 seated within a recess 13 operates,when otherwise free, to move the stem 9 to the open position. The yoke 8may be locked to the operating stem 9 by means of a catch 14 which ispivotally mounted within a recess 14* in the stem and adapted to engageat its inner end with the outer face of the yoke. The catch is normallyheld in its operative position by means of a spring 15. Thus it will beseen that when the catch is set, the stem may be moved in or out so asto carry with it the movable switch member but when the catch is trippedthe switch is opened through the action of the spring 11 which throwsthe movable switch members out of engagement with the fixed members.This opening movement of the switch member is independent of any-movement of the stem so that the switch may open while the operatingstem remains in its extreme inner position. The purpose in making theoperating stem separate from the switch member itself is to permit theoperating member to be rendered inoperative under predetermined circuitconditions, such, for example, as upon overload. In the form of theinvention shown, the switch is adapted for automatic release onoverload, and to this end a pair of electromagnets 16 and 17 in circuitwith the switch members are provided. These magnets have a. movablearmature member 18 adapted, when a definite current value is reached, tobe drawn against a nose 19 on the catch and thereby force the catch outof engagement with the contact-carrying yoke. Therefore, as soon as theoverload condition is reached, the catch is tripped and the switchopened, and so long as the overload condition remains it is impossibleto again set the switch. Any desired form of electromagnet may of coursebe used instead of the particular type shown, but the double magnet isconvenient since the yoke pieces 18 and 18' may be made to serve asguides and supports for the operating stem as shown.

In order to 'hold the operating stem in the switch-closing positionagainst the tension of the spring 12 as well as of the spring 11, asecond catch 20, also arranged within the recess in the stem, isprovided. This latter catch constantly tends to swing outward so as toengage beneath a fixed shoulder 21 when the stem is in theswitch-closing position. When, however, the catch 14 is closing of theswitch will energize the overload magnet and the switch will immediatelybe opened. Normally the switch iso ened by turning a handle or button 22on t e outer end of .the stem. This handle or button is held againstaxial-movement relative to the stem by means of a rod 23 secured at oneend to the handle or button and having an annular groove 24 near itsother end which engages a pin 25 in the stem. The handle or button istherefore held against axial movement uponthe stem but may revolvethereon. A torsion spring 26, arranged within the handle and having oneend fastened thereto and its other end fastened to the stem, normallyholds the handle in a position wherein a shoulder 27 abuts against a pin28 on the stem. When the handle is turned against the tension of thespring, a cam 29, formed on the lower end of the handle, engages aprojection 30 on the catch 14 and forces the catch out of engagementwith the movable switch member. During nor mal operation of the switch,therefore, the handle or button is pushed inward to set the switch andis rotated to cause the switch to open; and since the opening of theswitch is entirely independent of the outward movement of the button,there is 'no danger of causing the switch to open slowly due to holdingthe handle depressed or allowing it to move outward slowly. The movablearma-' ture is normally held out of engagement with the catch by meansof a spring 31 and,by adjusting the tension of the spring through thethumb-nut 32, the switch ma be made to release on any predetermined oad.

It will now be seen that the present invention provides in a simple andcompact structure a switch mechanism wherein the movable member isdisengaged from the fixed member with a snap action at all times, bothduring normal and abnormal conditions, and wherein it is impossible tomaintain the contacts in engagement during the predetermined abnormalcircuit conditions.

While the construction illustrated constitutes the preferred form of thepresent invention, it will of course be understood that various changesmay be made in the constituent elements and in their organization,without departing from the scope vof the present invention as viewed inits broader aspects.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. A circuit breaker comprising a movable contact, a longitudinallymovable operating stem on which said contact is slidably mounted, alatch for disengageably connecting said contact to said stem, anelectroresponsive tripping device for actuating said latch to releasesaid contact from said stem,

and restraining means for locking said stem immovable in switch closingposition.

2. A circuit breaker comprising a movable contact, a longitudinallymovable operating stem for moving said contact to close the switch, saidcontact and said stem being relatively movable longitudinally of saidstem, a disengageable latch for locking said contact to said stem,electroresponsive means for actuating said latch to release saidcontact, and a catch arranged to hold said operating stem immovable andthereby hold the switch closed.

3. A circuit breaker comprising cooperating relatively movable contacts,a movable operating member on which one of said c011- tacts is s idablymounted, a latch for locking said contact to said operating member,tripping means for actuating said latch to release said contact fromsaid member, and restraining means for holding said member immovable inswitch closing position, said means being operated by said contact asthe switch opens to release said'member.

4;. 'A switch comprising cooperating fixed and movable members, anoperating handle mounted to move in a definite path, a latch forconnecting said operating handle to the movable switch member, a catchfor locking the handle in the switch-closing position, a i

movable member mounted on said handle to move transversely of the pathof said handle into enga ement with said latch to trip it and there ypermit said switch member to move.

5. A switch comprising cooperating fixed and movable members, anoperating handle mounted to reciprocate, a latch, for connecting saidoperating handle to the movable switch member, a catch for locking saidhan- 3 tacts is slidably mounted, a spring for mov-,

ing said member to the open position, a dis engageable latch for rigidlyconnecting said contact to said member, electroresponsive means fortripping said latch to free said contact from said member, and a catchfor locking said member immovable to hold said contact in switch closingposition, said catch being tripped by the movable contact as the switchopens.

7. A switch comprising a cooperating fixed and movable member,. a springfor transverse to the plane of movement of said handle to trip thefirst-named catch.

8. A switch comprising cooperating fixed and movable members, a springfor moving said movable member out of engagement with the fixed member,an operating stem mounted to reciprocate, a catch for connecting saidoperating stem to said movable switch member, a second catch for lockingsaid stem in the switch-closing position, a member mounted on said stemto move in a plane transverse to the movement of said stem and therebytrip the first-named catch, and an electromagnet also arranged to tripthe first-named catch under determinate circuit conditions.

9. A circuit breaker comprising cotiperating relatively movablecontacts, an operating member mounted to reciprocate and on which one ofsaid contacts is slidably mounted, a latch for locking said contact tosaid member, a spring for separating said contacts, a catch arranged tolock said member immovable in the switch closing position,

means rotatably mounted on said member for tripping said latch, and anelectromagnet arranged to trip said latch in response to abnormalcurrent in the circuit. v

'10. In a switch, a fixed contact member, an operating device arrangedto reciprocate toward and from said contact member, a movable contactmember slidably mounted on said operating device, .a spring for movingsaid movable contact member out of engagement with the fixed contactmember, a catch for locking said movable contact member to saidoperating device, an electromagnet for releasing said catch underdct-erminate circuit conditions, and means controlled by said movablecontact member arranged to hold said operating device in theswitch-closing position.

11. In a switch, a fixed contact member, an operating device arranged toreciprocate to and from said contact member, a movable contact memberslidably mounted on said operating device, a s ring for movingsaidmovable contact mem er out of engagement with the fixed contact member,a catch for locking said movable contact member to said operatingdevice, an electromagnet for releasing said catch when the -circuit isoverloaded, means on said operating device also arranged to release saidcatch, and means controlled by said movable contact member arranged tohold said operating device in the switch-closing position.

12. In a switch, a switch contact member, an operating device arrangedto reciprocate toward and from said contact member, a movable contactmember slidingly mounted on said operating device, a spring for movingsaid movable contact member out of engagement with the fixed contactmember, a catch carried by said operating device for locking saidmovable contact member to said operatin device, a movable portion onsaid han 1e for releasing said catch, and a second catch carried by saidoperating device for locking said operating device in switchclosingposition, said latter catch having a portion arranged in the path ofmovement of the movable contact member.

13. A circuit breaker comprising coiiperating relatively movablecontacts, a reciprocating operating member on which one of said contactsis slidably mounted, a latch for locking said contact to said, operatingmember, a spring for separating said con tacts, a second spring formoving said operating member out of switch closing position,electroresponsive means for tripping said latch to release said contactfrom said member, and restraining meansfor locking said operating memberimmovable 1n switch closing position against the tension of saldsprings, said restraining means being controlled by said movablecontact.

14. In aswitch, a movable switch member, an operatin handle arranged tobe moved axially to cise the switch, a latch between the handle and theswitch released by the rotation of the handle, restraining meanscooperating with said handle to hold the switch closed and meansoperative upon release of the latch by said handle to move said movableiswitch member axially of the handle to open the switch.

15. In a switch, fixed and movable contact members, an operating memberfor closing the switch upon an axial movement, a latch between theoperating member and the movable contact member, a handle revolublymounted on the outer end of said operating member to release said latch,restraining means cooperating with said handle to hold the switch closedand means for moving said movable contact member axially of theoperating member to open the switch when the latch is released. I

16. A circuit breaker comprising cooperating relatively movablecontacts, an operating member for said contacts mounted to move in adefinite path to close said circuit breaker and to move transversely ofsaid path to trip said circuit breaker, restraining actuating said latchto permit said contacts means for holding said operating member toseparate.

. 1b in circuit closing position, a latch for dis- In Witness whereof, Ihave hereunto set engageably connecting one of said contacts my handthis 21st day of March, 1906.

to said operating member, and associated] MAX FUSS. with said operatingmember to be tripped Witnesses:

by a transverse movement of said member, 7 MAX HAMBURGER,

and an electroresponsive tripping device for JULIUS RUMLAND.

